Equity and Equity Compensation - Narrative (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Capital stock shares authorized	2,000,000,000.0
Common stock, shares authorized	1,500,000,000	1,500,000,000
Common stock, par value (usd per share)	$ 0.0001	$ 0.0001
Preferred stock, shares authorized	500,000,000
Treasury stock acquired, weighted average cost per share	$ 19.40	$ 17.70
Share-based compensation arrangement by share-based payment award, number of shares authorized	163,000,000
Common stock, capital shares reserved for future issuance	31,000,000
Share-based compensation	$ 105,000,000	$ 76,000,000	$ 81,000,000
Employee service share-based compensation, nonvested awards, compensation cost not yet recognized	$ 74,000,000
Share-based compensation arrangement by share-based payment award, equity instruments other than options, nonvested, shares	2,800,000
Share-based compensation arrangement by share-based payment award, options, outstanding, shares	2,800,000
Share-based compensation arrangement by share-based payment award, options, exercisable, weighted average exercise price	$ 21.22
Share-based compensation arrangement by share-based payment award, options, exercisable, shares	2,200,000
Employee service share-based compensation, tax benefit from compensation expense	$ 0
Excess tax benefits	$ 33,000,000